I use a modified garden sprayer. I clean all of my lines at the same time reusing the BLC. I want to build a pond pump based recirculating system, but that is low priority right now.
The hardest part of the build was finding a liquid post with the right threading. I took the fitting to my LHBS and went through a bin of posts until I succeeded.
That's a long thread - I didn't read much of it, but I liked its simplicity and wanted to upgrade from the pump bottle beer line cleaning tool I previously made, that was a pain because it screws onto the liquid line flare fitting rather than directly into a QD.
Anyway, so I bought the FloMaster bottle at Home Depot, and found a Watts brand brass adapter at Lowe's that, similar to the initial post via the link, connected the ball lock liquid post to the FloMaster with a single fitting. It's probably also found in the HomeBrewTalk thread, but here's the Watts brand brass compression adapter fitting that will work to connect the FloMaster to typical Pepsi threads of a ball lock liquid post:
WATTS Part# LFA-117 labeled as Compression / Lead Free / Adapter 3/8 in OD x 3/8 in FIP
It is NOT a flare fitting.
Caveat: the 3/8 OD post on the adapter only turned several turns, and just a tad loosely into the liquid post, but it was plenty of purchase to create a good seal when using teflon tape. I had to wrap a lot of teflon tape (7 - 10 wraps) on the adapter male side, and 5 - 6 wraps on the FloMaster plastic male threads to get a great seal. But tightened down this works well - nary a drip when the bottle is pumped up with pressure.